This bi-fold door restrictor is available in both 335mm and 500mm long and fits in the outer frame roller channel which is 19mm deep. 
 
It is "hold-open" and by moving the restrictor laterally in the channel, many angles of opening and "holding" are achievable (from under 90 degrees up to 130 degrees). 
 
	
Friction can be adjusted by means of a "Phillips" screw. 
	
All materials used are durable and non-corrosive. 
	
Restrictors are available in 430 Stainless Steel as standard.